I saw a very bright light night before last (25th Jan 2009, between 7pm and 8pm UTC) [UTC=GMT; actual U.K.

time] while driving a truck south from Bristol, U.K. 90 miles down to Devon, on the M5 motorway.

It was in the South-Western sky, and kept getting even brighter so I could even see the diffused light through cloud, and then dimming and completely disappearing before reappearing again, and undulating in it's intensity.

The frequency at which it grew and faded was several minutes, being there and going again. It would only take a matter of 5 seconds or less to fade or to reappear in those intervals, and when it faded it would quickly fade to a faint dot before disappearing, rather like those old TV sets when they were switched off.

It was not that it was going behind cloud for this would happen in clear sky, and when it was at it's brightest and cloud was obscuring it, it illuminated the cloud somewhat. It was as bright as aircraft landing lights, but obviously it's behavior and position seems to rule that out. While I was in Devon, my friend could still see it some 60 miles away in Bristol, when I called her.

(She, and my mother-in-law, have apparently been observing this strange light for up to a week, usually in the same sector of the sky). I observed this phenomena for about an hour as I drove south, seeing it up to my right in a roughly SW direction at about 50° above the horizontal plane. My latitude was about 51°N.(2°W).

At first I thought it was an aircraft, but it was too high to have its landing lights on, and after a short amount of observation realized it was not behaving like an aircraft.

It maintained what appeared to be a stationary position from my perspective for the hour I observed it, while I drove south.

It certainly was not Venus, this I know for certain, I recognize that particular celestial body. Could it be some kind of supernovae? Or perhaps a very high and bright military craft, more likely in orbit.